Bug 30680
| Summary: | uptime and w utilities lie about real uptime | ||||||
|---|---|---|---|---|---|---|---|
| Product: | Base System | Reporter: | vova <vova> | ||||
| Component: | bin | Assignee: | Crist J. Clark <cjc> | ||||
| Status: | Closed FIXED | ||||||
| Severity: | Affects Only Me | CC: | hackers | ||||
| Priority: | Normal | ||||||
| Version: | 5.0-CURRENT | ||||||
| Hardware: | Any | ||||||
| OS: | Any | ||||||
| Attachments: |
|
||||||
On Thu, Sep 20, 2001 at 03:21:08PM +0400, Vladimir B.Grebenschikov wrote:
> why utility increases uptime on 30 seconds ??
> Is any real reasons for it ?
It adds 30 because it wants to round the number of minutes to the
nearest minute, instead of rounding down. Unfortunately this isn't
a sensible thing to do if you are also going to display the number
of seconds.
David.
On Thu, Sep 20, 2001 at 05:40:05AM -0700, David Malone wrote: > The following reply was made to PR bin/30680; it has been noted by GNATS. > > From: David Malone <dwmalone@maths.tcd.ie> > To: "Vladimir B.Grebenschikov" <vova@express.ru> > Cc: FreeBSD-gnats-submit@freebsd.org, freebsd-hackers@freebsd.org > Subject: Re: bin/30680: uptime and w utilities lie about real uptime > Date: Thu, 20 Sep 2001 13:31:49 +0100 > > On Thu, Sep 20, 2001 at 03:21:08PM +0400, Vladimir B.Grebenschikov wrote: > > why utility increases uptime on 30 seconds ?? > > Is any real reasons for it ? > > It adds 30 because it wants to round the number of minutes to the > nearest minute, instead of rounding down. Unfortunately this isn't > a sensible thing to do if you are also going to display the number > of seconds. The only time this is noticed is when the time is printed in seconds. This should fix it, Index: src/usr.bin/w/w.c =================================================================== RCS file: /export/ncvs/src/usr.bin/w/w.c,v retrieving revision 1.48 diff -u -r1.48 w.c --- src/usr.bin/w/w.c 2001/07/26 19:20:13 1.48 +++ src/usr.bin/w/w.c 2001/09/20 19:00:57 @@ -452,13 +452,15 @@ if (sysctl(mib, 2, &boottime, &size, NULL, 0) != -1 && boottime.tv_sec != 0) { uptime = now - boottime.tv_sec; + /* Round to nearest minute. */ uptime += 30; days = uptime / 86400; uptime %= 86400; hrs = uptime / 3600; uptime %= 3600; mins = uptime / 60; - secs = uptime % 60; + /* Undo rounding to calculate uptime in seconds. */ + secs = (uptime - 30) % 60; (void)printf(" up"); if (days > 0) (void)printf(" %d day%s,", days, days > 1 ? "s" : ""); I will commit the fix later unless someone has comments. -- Crist J. Clark cjclark@alum.mit.edu State Changed From-To: open->analyzed Fix being committed to CURRENT. Responsible Changed From-To: freebsd-bugs->cjc Made the fix in my repo doing some checks and will commit. On Thu, 20 Sep 2001, Crist J. Clark wrote: > On Thu, Sep 20, 2001 at 05:40:05AM -0700, David Malone wrote: > > It adds 30 because it wants to round the number of minutes to the > > nearest minute, instead of rounding down. Unfortunately this isn't > > a sensible thing to do if you are also going to display the number > > of seconds. > > The only time this is noticed is when the time is printed in > seconds. This should fix it, > > Index: src/usr.bin/w/w.c > =================================================================== > RCS file: /export/ncvs/src/usr.bin/w/w.c,v > retrieving revision 1.48 > diff -u -r1.48 w.c > --- src/usr.bin/w/w.c 2001/07/26 19:20:13 1.48 > +++ src/usr.bin/w/w.c 2001/09/20 19:00:57 > @@ -452,13 +452,15 @@ > if (sysctl(mib, 2, &boottime, &size, NULL, 0) != -1 && > boottime.tv_sec != 0) { > uptime = now - boottime.tv_sec; > + /* Round to nearest minute. */ > uptime += 30; > days = uptime / 86400; > uptime %= 86400; > hrs = uptime / 3600; > uptime %= 3600; > mins = uptime / 60; > - secs = uptime % 60; > + /* Undo rounding to calculate uptime in seconds. */ > + secs = (uptime - 30) % 60; > (void)printf(" up"); > if (days > 0) > (void)printf(" %d day%s,", days, days > 1 ? "s" : ""); > > I will commit the fix later unless someone has comments. Just add 30 in the one place where it is needed: mins = (uptime + 30) / 60; Bruce On Thu, Sep 20, 2001 at 01:20:01PM -0700, Bruce Evans wrote: > On Thu, 20 Sep 2001, Crist J. Clark wrote: > > On Thu, Sep 20, 2001 at 05:40:05AM -0700, David Malone wrote: > > > It adds 30 because it wants to round the number of minutes to the > > > nearest minute, instead of rounding down. Unfortunately this isn't > > > a sensible thing to do if you are also going to display the number > > > of seconds. > > > > The only time this is noticed is when the time is printed in > > seconds. This should fix it, > > > > Index: src/usr.bin/w/w.c > > =================================================================== > > RCS file: /export/ncvs/src/usr.bin/w/w.c,v > > retrieving revision 1.48 > > diff -u -r1.48 w.c > > --- src/usr.bin/w/w.c 2001/07/26 19:20:13 1.48 > > +++ src/usr.bin/w/w.c 2001/09/20 19:00:57 > > @@ -452,13 +452,15 @@ > > if (sysctl(mib, 2, &boottime, &size, NULL, 0) != -1 && > > boottime.tv_sec != 0) { > > uptime = now - boottime.tv_sec; > > + /* Round to nearest minute. */ > > uptime += 30; > > days = uptime / 86400; > > uptime %= 86400; > > hrs = uptime / 3600; > > uptime %= 3600; > > mins = uptime / 60; > > - secs = uptime % 60; > > + /* Undo rounding to calculate uptime in seconds. */ > > + secs = (uptime - 30) % 60; > > (void)printf(" up"); > > if (days > 0) > > (void)printf(" %d day%s,", days, days > 1 ? "s" : ""); > > > > I will commit the fix later unless someone has comments. > > Just add 30 in the one place where it is needed: > > mins = (uptime + 30) / 60; That won't actually work correctly. For example, if you were at, 1 day 23:59:45 Just adding the 30 seconds when calculating 'mins' would produce, 1 day 23:00 Instead of the correct, 2 days 00:00 -- Crist J. Clark cjclark@alum.mit.edu State Changed From-To: analyzed->closed Fix MFC'ed into STABLE. |
Just after very fast boot uptimealways shows more than 30 sec. looking to src/usr/bin/w/w.c: if (sysctl(mib, 2, &boottime, &size, NULL, 0) != -1 && boottime.tv_sec != 0) { uptime = now - boottime.tv_sec; uptime += 30; ====================== ^^^^^ days = uptime / 86400; uptime %= 86400; hrs = uptime / 3600; uptime %= 3600; mins = uptime / 60; secs = uptime % 60; (void)printf(" up"); why utility increases uptime on 30 seconds ?? Is any real reasons for it ? How-To-Repeat: Boot and run uptime